Create ktx initLoader / restartLoader methods

Rather than create a LoaderManager.LoaderCallbacks
instance, allow Kotlin users to pass in the Loader
directly and lambdas for managing the callback
methods.

Test: newly added test
Change-Id: I52e87a7f55f59a24f63362893b6c1e09af25b08a
diff --git a/settings.gradle b/settings.gradle
index a3cb6f2..4a14a1f 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -127,6 +127,7 @@
 includeProject(":lifecycle:lifecycle-viewmodel-ktx", "lifecycle/viewmodel/ktx")
 includeProject(":lifecycle:lifecycle-viewmodel-savedstate","lifecycle/viewmodel-savedstate")
 includeProject(":loader:loader", "loader/loader")
+includeProject(":loader:loader-ktx", "loader/loader-ktx")
 includeProject(":localbroadcastmanager", "localbroadcastmanager")
 includeProject(":media", "media")
 includeProject(":media2:media2-common", "media2/common")